memory card corrupt

[vinsent10]

Hi I recently got into emulators and downloaded dolphin because I wanted to play wind waker. When I got it to work I played it all the way to the dragon roost island. But when I got to the part with the weird heat effect it became unplayable so I looked for a fix, found out that there's a even newer version (4.2) and downloaded that instead, but when I start the game it says my memory card is corrupt, what do I do?